Novel Filtering Duplex Antenna Using Split-Ring Resonators

This letter presents a novel filtering duplex patch antenna using split-ring resonator (SRR). The proposed duplex antenna consists of a parasitic patch, a radiating patch and two sets of resonator-based filtering channels as feeding network. The parasitic patch is designed for improving the bandwidth and the gain of the antenna. Then, a novel dual-band radiating patch is achieved by loading 15 via-holes. Two sets of SRR resonators are designed to improve the isolation between transmitting (TX) and receiving (RX) signal. For demonstration, the duplex antenna is fabricated and measured. The measured impedance bandwidth of the TX and RX channel is 5.5% (2.31-2.43GHz) and 4.2% (2.64-2.75GHz). The antenna shows an isolation of 31dB.